High Energy Astrophysics department at IKI, Moscow, is carrying out research in various fields of X-ray astronomy: physical processes in the vicinity of compact sources of x-ray emission, x-ray observations using Russian space observatories MIR/KVANT and GRANAT, development of scientific instrumentation for the SPECTRUM-X-GAMMA mission and International Space Station (ISS), participation in the INTEGRAL project and observations on the RTT-150 optical telescope.